Drive unit for domestic ironing machines or the like



Their Attorn e y.

8 mm P OWJ m m v PM W .m WW0 June 3, 1952 J. c. WORST El'AL DRIVE UNIT FOR DOMESTIC IRONING MACHINES OR THE LIKE Filed Dec. 2, 1949 Patented June 3, 1952 DRIVE UNIT FOR DOMESTIC IRQNiNG MACHINES R .THELIKEl Joseph-C; Worst and-Carl S." Day-ton, Bridgeport;

Conn,- assignors to Genera-lz-El'ectric Company, a :corporation .of New York Application December 2, 1949'. serial No. 130,656

lil filaims.

Our invention relatesto an improveddomestic ironing machine 'of the type having-' mutually cooperating buck and shoe element between which the articles are pressed; and particularly relates to improved means for timing the opera tionof on of the pressing elements withrespect to the approach of the other elementto ultimate operating position."

The objects of our inventioninclude' the provision of improved means for automatically operatingthe buck and 'the shoe'in" a predetermined timed relationship; the provision of driving means common to both elements and simultaneously biasing the same to operating positiong-the provision of simple, effective means fordelaying the operation of one pressing element until the other has reached operating positionnotwithstanding the employment ofa common driving means; 'and the provision of means utilizing the driving means for effectively controlling the-return'of' the re spective pressing elements to their non-operative or home position.

A presently preferred embodiment o f"our in vention provides a frame structure arranged to have a table-like workingsurfa'ce ionWhich -is l'ocateda main cylinder unit of ,ajhydraulicmotor system. The motor .u'n'itflincludes a piston unit suitably carrying thebuckstructure ,for move= ment between a home or retracted positionand a projected or operatin position. To propelthe piston for projection of the buckintd operating position we have found it"expedie'nt to use the hydraulic pressure generator .which'is 'shown'in similar relationship in the Wandwell, Jr.', Patent No. 2,135,266, granted November 1 1938 for Ironing Machine. We mounti'th conventional heated shoe on a relatively conventional U-shaped arm or carriage pivoted relative to the "buckas by pivotal attachment tofthe main "cylinder so that the shoe carriage may be swung in a plane transversely of the buck tobring the shoe-from its home position intoanpperativejposition -in registry with the buck." 'Weoperate'the shoe carriage from a pistonpperating within a second cylinder which is'in communication with thefirst-L An important feature of'our inventionresides-in utilizing the single *fluid pressure generating means for the propulsion of both pistons while effecting the movement-of the-respective press elements in a predetermined timed relationship. Because in the type of ironer-whichwe-have chosen for exemplifying-our invention the buck is driven upwardly against the previously- Josi tioned shoe; we provide means .for holding-thebuck against movement during the pperationpf 2r. the shoe carriage, and automatically release the holding means by shoe carriage action'as'thecarriage comes into its operating position. Follow ing-the' release of the buck it will "be driven upwardly into pressing relationship with the shoe by'the operation of its piston. Inthis manner, we insure that the shoe will be in position for accurate registry with the buck. In types of ironers' in which'the' shoe exerts pressure against a-previously positioned buck, our invention could as" readily be adapted to restrain'the shoe until the buckhad beenpositioned. An effective featureofour invention derives from check valve means which immediately upon'upwa'rd movementof the buck closes'against'return flow of hydrauli-c fluid fromthe shoe cylinder so as to provide a locked body of'liquid holding the shoe and its carriage firmly in position during the pressing operation: The 'c'heck'valve maintains the shoe carriage in itsele'veated position until means controlled "by the return of the buck piston substantially to its home position opens the valve to permit return-flow from the shoe carriage cylinder to the main cylinder; The carriage is thus per-- mitted to returnto its home position. The controlledliquid flow provides effective fluid dampenersfo'r' cushioning the return movement of, the buck and shoe and thus eliminates the necessity for the usual arrangement of dampening springs or dashpot'accessories: 1 Further features and advantages of the inventionwill be apparent :from the accompanying drawingread in connectionwith the annexed s e i ic ion: In the dr w n F 1 is a partia side elevation jofan ironingmachine embodying our invention; the machine being .shown transverse sectional elevation. Fig. 2 is an enlarged fragmentary view in vertical section of. the main and vauxiliary piston means; particularlyv showing the check valve arrangement controlliiigcommunication' between the main and auxiliary cylinde'rs." Fig. 3 is airagmentary ,view showing the flow of fluid from the-main. cylinder into the shoe operating cylinder passage during the beginning of operation of the machine.

As 'shown in'ffig. 1, the fiatplate ironing machinewhichuwe have chosen to illustrate our invention includes a rigid frame structure vl constructed in table-like form ,to provide" a rigid .top surface .2. A main hydraulic cylinder 3 is providad with flange means '4 intermediate itsnend-s to afford means. by yvl liph1131.116,cylir'lder 3 may. .be afiixed to th irame The flan e. is ane la y related "With respe'ct'to the cylinder axis. so as to supportthe cylinder in a'iorwardly inclining position. It should be understood, however, that when viewed in front elevation the cylinder extends vertically with respect to the table top. Pursuant to conventional flatplate ironing practice the buck is secured to the upper extremity of a piston 6 which operates within the cylinder 3. As is known in the art the buck 5 is generally of elongate rectangular shape, and is padded to provide a cushioned surface on which the articles to be ironed are placed by the operator. Also as is known in the art fiatplate ironers utilize a shoe 1 having a smooth, heated ironing surface coextensive with the surface of the buck and arranged to be brought into registry with the buck. For this purpose, the shoe is mounted on a carriage 8 which is pivoted relative to the buck. When the shoe carriage is suitably rotated the shoe is brought into its operating position above the buck and the latter may then be driven upwardly so that the clothes thereon may be pressed between the buck and the shoe. In Fig. 1 the full line representation shows the buck and shoe in a retracted or home position and the dotted lines show the respective elements in pressing relationship. It might be noted here that the normal extent of upward movement of the buck is of the order of from inch to 1 inch.

The shoe carriage 8 is desirably of relatively heavy metal stock and is of relatively wide channel-like cross section so as to afford a suitably rigid structure. For pivotally mounting the shoe we have provided ears 9 depending from the cylinder 3 at opposite sides thereof. An extension IE1 of each side wall of the shoe carriage S registers with the adjacent ear and individual pivot attachments, or a suitable shaft Ii extending from one to the other ear may be employed. It will be obvious that other ways of pivotal mounting of the shoe carriage may occur to those skilled in the art; we have chosen to illustrate what we now consider to be a suitable mounting system.

As previously stated, we incorporate with the piston B a hydraulic pressure generating unit which is basically old and well known in the art. In the construction shown in Fig. 2 the piston is provided with a chamber within which is mounted a motor [2 having a shaft extending through a suitable gland to terminate in an impeller I4 operating within a pump chamber [5. It is practical to form the pump chamber by suitably machining out a flange 16 which forms the piston head. Flange I6 is suitably secured to a flange I1 welded or otherwise secured to the body of the piston. The flanges cooperate to receive a piston ring l8. Other flange members disposed intermediate the length of the piston 6 provide for an upper piston ring 20. A central web portion of the flange l1 provides an inlet 2| for the pump housing. It should be understood that the cylinder 3 normally contains a charge of liquid, preferably a light oil, to the approximate level designated 0. L. in Fig. 2. The cylinder thus serves additionally as a reservoir of liquid to be drawn on by the pump impeller 14. We provide the usual side wall passages 22 and a foraminated guard screen 23 through which the liquid actually passes to the pump inlet 2 I The discharge from the pump travels by way of a passage 24 and ports 25 through the cylinder head to the cylinder space 26 forwardly of the piston head, driving the piston and buck upwardly. Relatively larger ports 21 pass through the piston head assembly externally of the wall of the piston 6 to provide a direct return path from space 26 to the oil reservoir above the piston head. Controlling said ports 25 and 21 is a slide valve 28 operating within passage 24 and biased by spring 29 normally to close ports 25 and open ports 27. It will be understood that there are preferably two sets of ports and two slide valves. Under the pressure of discharging oil, the valves are urged outwardly to open ports 25 and close ports 21, thus preventing a return of oil to the reservoir from space 26. The piston returns by gravity to home position, the pump having been stopped, and the large return flow ports 21, then open, facilitate return of oil to the reservoir. This valve controlled port arrangement is disclosed and claimed in the copending application of J. F. Young, Serial No. 134,473, filed December 22, 1949, for Operating Mechanism for Domestic Ironing Machine and assigned to the assignee of the instant application. It will be understood that the operator controls the motor l2 by any conventional means, such as the usual foot pedal or knee operated switch (not shown).

In ironers of the type shown in the said Wardwell, Jr., Patent No. 2,135,266, motor operation is effective immediately to drive the piston 8 and its thereon mounted buck upwardly into relationship with a shoe which had previously manually been brought into operating position. We provide means for automatically bringing the shoe into registering position before the buck is permitted any substantial rise even though we utilize the pressure generation means of the piston 6 for drivin the shoe carriage. As most clearly appears in Fig. 2 we utilize a second cylinder 30 within which operates a conventional piston 3|, and operatively connect the piston rod 32 thereof with the shoe carriage 8 by an intermediate pivoted link 33 which is centered with respect to the shoe carriage. A convenient means of securing the link 33 to the shoe carriage is to provide ears 34 depending from the side walls of the carriage, and thread a pivot rod 35 through the ears and link. Spacer sleeves 36 may be carried on the rod and interposed between the side walls of link 33 and the adjacent ears 34 to maintain the centered position of the link. We have shown a screw threaded cylinder head 3'! and a piston rod gland 38 although obviously other arrangements are within the scope of those skilled in the art. It will be understood that it is not necessary to have the cylinder 30 carried by the cylinder 3; it is only necessary that cylinder 38 be suitably supported in the frame structure. We believe that manufaotur ing economies will dictate that cylinder 30 be cast en bloc with cylinder 3. Such an arrangement, for example, makes it practicable to drill the communicating conduit 40 in the thickened head portion of cylinder 3. A remotely disposed cylinder 30 would obviously require the use of tubing or the like, requiring connection fitting and introducing leakage problems. For reasons later explained, we control the communication between the cylinders 30 and 3 by a check valve which prevents return flow from cylinder 39 so long as piston B is away from home position. Suitable check valve means may comprise a ball 4| biased by a spring 42 normally to seat against an orifice 43 communicating with the chamber 26. We prefer that with the piston 6 in its home position shown in Figs. 2 and 3 the ball check valve 4| be kept unseated by the engagement therewith of a projection 44 extending from the piston head l6. As indicated in Fig. 3, the initialoperation of the pump l4 causes oil to flow .aesaeos immediatel throughtheiorifice 43 into tli'e pas sage 45 to the cylinder 38,iisaidpassage Entering the cylinder below itheipiston :31: as viewed :inIFig. 2. In order to recapture an-ydiquidwhich may work past the piston .31! 'we provideia communicating port 45 at aboutithe upperoperatingposi tion of the piston. each stroke of saidipiston, oil which may lie .thereon passes intourthe reservoir of cylinders."

The timed relationship 1 ot ithe Ibuck L and. :the shoe carriage 8 is accomplished 'byvmeanstrestraining the upward movement of the piston .6 during a predeterminedextent of movem'ent of the carriage. 8. In addition to improvingthe-operation of the ironing-= machinebytaccurately timing the operation of ronepressingelement with respect to the other, T011! invention-imposes no unreasonable burden uponthe pressure generator' notwithstanding. the double duty :01: the generator as compared with .irtmers of the type of the said Wardwell patent in whichlzthe shoe :is manually operated. We may-wherefore :us'efi -a small, compactgenerator. The presently preferred embodiment of ouzr invention utilizes ea mechanical latch to hold the pistons; against movement and provides means responsive :to movement of the carriage]; :for 'tripping fthe latch when piston operation:is -to-scommence. Accordingly, and as somewhat schematically shown in Fig. 1, we provide the pistontfi 'withian outwardly extending .lugztfi "of adequate structure and swingably suspend :irom said lzuga latch member All which terminates in the latching head All. For cooperation with-the latching head 6,8 we secure to the table top12 arigid bl'ock' 5il having a suitablynotched end portion 5| .for engagement with the latching head Aspiring 52 suitably carried on the cylinder-3 "urges the latch member 4.1 clockwise of and therefore tends to maintain the latching head and the block in engagement. 1 By v:making head AS suitably longer than the piston'travel, the head will always remain inoperative relation to'the block. It will be understood that the lugiflfi-is suitably offset with respect to the *axis ofithe cylinder 3 so that the respective latching bers may lie alongside of :the cylinder '35 as shown in Fig. 1. It will also be understood that a balanced arrangement man' be made :ifdesired 'witha second latch member Mand'block 50"disposed on the opposite side ofthe cylinder 30'';

When the respective .pre'ssing'elements same in their home position, the latch 41 holds thetpiston 6 against upward movement. Withthepistoni-so held, the impeller provides"adequate-hydraulic pressure for operationrof the piston :3 I; amt-the rising piston 31 causes a'clockwise'rotation of the shoe carriage 8. As the-.carriag'eapproaches its operating position, it tensions suitable-spring meansfor example,-a leaf spring :54 "engaged :by the top wallof the carriage -so that WhGII'ISHitable stop means not'shown) establishing the operating position of the shoearmzisreached, spring 54 will have sufiicientenergymocinitiaterthe return of the carriage :atthe rproper tim'e'e To release the latch fl'iailt'er'the sli'oe carriage has been brought into operatingiposition wel iave employed a trip rod 53 on the carriage ii in alignment with the latch head 48. As the carriagerswings into registering position the rod 5 53 engages the- -sloping forward surface of the latch head and drives it to therig'ht of Fig. 1 'against tlre pressure of spring'52 to release' the latch head-from the block 50. lhepiston fi is 'tlfiereupon free to rise and operates topropelthebuk' upwardly into pressing relationship with theshoe Spring 52 holds latch head 4'8 slidably in contact 7 with block-50' as the: latch .riseswith the buck. Trip rod 53 may be screw threaded-toperm-i-t adjustment of. theinstant orrelease-of latch 41;" As the-piston fi risesthe ballvalve Aliollo'ws it upwardly to closethe orifice- 43T The small area of orifice 43 renders the unitpressure within chamber '26 ineffective to-hold-ithe-valve open against the strong biasot its mounting spring A2. The liquid is thereiore trapped within the cylinder 30 andac'ts to preventcounterclockwise move- .mentof the shoe carriage 8. The carriage is thus maintained steadily iii-registry with thebuck as the latter exerts ironing-pressure thereagainsh The return of the-buck and shoe to homeposition -is accomplished'by opening the motor oir cui t 12 whereupon the slide valve 28 'is drivcn leftwardly of: Flaw- 3 by its biasing-spring "28 to opentheport orpo'rtsfl tor the return "flow'of liquid from--chamber 25 to the liquid-reservoir. The weightof the piston 6 and its buck is ordinarily sufiicient to return the pistonto its-home position. As the piston head approaches home position the valve A! will be opened. whereupon the reaction-of spring 54' against the shoe carriage will throw-the carriage :throug'h the angular distance necessary for the-centerof gravity of the carriage topass beyond-the pivot H for completion-of the-return of the carriage by-g-ravstood that the-buck and the shoe carriage may be spring biased ior enforced .return ifdesired. The hydraulic system provides aneveiz available shock absorbing system so that even using powerful spring means to drive the elements to home position thereturhtosaid position will be without shockor jar.

It will beob'served that latch-41 'will'no't resea't until shortly after the shoe carriage B heginsits return movement; because of the continuing en gagementbetween rod 53 and the latch head during the piston-stroke. The operator may"-.bump the" buck against-the shoe by dot-energizing and then quickly reenergizing the pump motor after bringing the buck initiallyinto' ironing position. Such bumping operation, whenrskilliu lly .done, willin some instances improve theironingnf the articles. l

While we have shown a zparticularaemhodiment of our 'inventionit will beunderstood of course,

that we do not wishto be limited thereto since many modifications may .betmade'; and We :therefore contemplate by the appendedclaims toacover any suchmodifications as fall the. true spirit and scope of our invention.

What we claim as new'zand desire'torsecure z-by Letters Patentof the United States is:

1. An ironing machine comprising a pair of mutually cooperating press elements-individually adaptedto be brought from a home position to an operating position, means for simultaneously biasing said elements into'movement toward their respective operating positions, means for =releasably holding one of said elementsagains't move ment,and means operated by-saidot-her element upon movement thereof to release said holding means.

2. An ironing machine :comprisinga frame, a buck, meansior supportingsaidtbukiur movementfrom aiiome position'to an'operativejposi tion, a shoe, means for supporting saidshoeror movement from a home position to an operative position for cooperation with said buck, means common to said buck-supporting and said shoesupporting means to bias the same simultaneously toward their respective operating positions, means releasably holding said buck against movement, and cam means operated" upon movement of said shoe to release said holding means.

3. An ironing machine comprising a frame, a cylinder supported thereon, a piston in said cylinder, a buck on said piston, means for driving said piston in said cylinder, a shoe, a shoe carriage pivoted relative to the buck and swingable in a plane transversely thereof to bring the shoe into registry with said buck, means actuated by said piston-driving means to bring the shoe carriage into said registering position, means for temporarily holding said buck against movement relative to said cylinder during operation of said piston-driving means, and means carried by said shoe carriage to release said buck-holding means upon movement of said shoe carriage to a predetermined position.

4. An ironing machine comprising a frame, a cylinder supported thereon, a piston in said cylinder, a buck on said, piston, means for driving said piston in said cylinder, a shoe, a shoe carriage pivoted relative to the buck and swingable to position the shoe in registry with said buck, means actuated by said pston-driving means to bring the shoe carriage into said registering position, a latch carried by said buck and engage able with said frame to hold the buck against movement relative to said frame, and means perated by said shoe carriage during its movement to said registering position to effect the release of said latch to allow movement of said buck.

5. An ironing machine comprising a frame, a

cylinder supported thereon, a piston insaid cylinder, a buck on said piston, hydraulic pressure generating means in said cylinder to propel the piston therein, a shoe, a shoe carriage pivoted relative to the buck and swingable to a position in which the shoe will be in registry with the buck, means for bringing said shoe carriage into said registering position, a latch carried by said buck and engageable with said frame to hold the buck against movement relative to said frame, and means mounted on said carriage for releasing said latch at the completion of'a predetermined movement of said shoe carriage.

6. An ironing machine comprising a frame, a cylinder supported thereon, a piston in said cylinder, a buck on said piston to be moved thereby from a retracted position to a pressing position, means for propelling said piston, latch means between said frame and said buck to hold the buck against the efforts of said piston-propelling means, means for automatically rendering said latch effective at each return of the piston to retracted position, a shoe, a shoe carriage for movement relative to said buck, means for bringing said carriage into position with the shoe in registry with said buck, and means on said shoe carriage for striking said latch to release the same as the carriage is brought into said registering position.

'7. An ironing machine comprising a frame, a cylinder supported thereon, a piston in said cylinder, a buck on said piston, means for introducing hydraulic pressure into said cylinder ahead of the piston to propel the same, a shoe, a shoe carriage pivoted relative to the buck and swingable in a plane transversely thereof to bring the shoe into registry with the buck, a second cylinder fixed relative to the frame, a piston there- .in, means interconnecting said cylinders to feed said second cylinder with fluid under pressure from the first cylinder for driving said second piston, means connecting said second piston and said shoe carriage for operation of said carriage thereby, means for holding said brick against movement during operation of the second piston, and means effective as the shoe carriage comes into registering position to release the buckfor operation of the first piston.

8. An ironing machine comprising a frame, a cylinder supported therein, a piston in said cylinder, a buck on said piston, means for discharging fluid under pressure forwardly of said piston to propel the same from a home position to an operating position, a shoe, a carriage for said shoe and arranged to be propelled from a home position to an operating position, a second cylinderflxed relative to said frame, a piston in said cylinder and connected to said carriage for bringing the carriage into operating position, conduit means interconnecting said cylinders to feed said second cylinder with fluid to operate the piston therein, check valve means in said conduit to bar return flow of fluid from said second cylinder, means operated by the first piston when in home position to open said check valve means, means for releasably holding said piston in home position, and means operated by said shoe carriage to release said holding means after predetermined travel of said carriage, said first piston releasing said check valve means at the commencement of piston travel.

9. An ironing machine comprising a frame, a cylinder supported thereon, a piston in said cylinder, a buck on said piston, means for discharging fluid under pressure forwardly of said piston to propel the same from a home position to an operating position, a shoe, a carriage for said shoe and arranged to be propelled from a home position to an operating position, a second cylinder fixed relative to the frame, a piston in said cylinder for bringing the carriage into operating position, conduit means interconnecting said cylinders to feed said second cylinder with fluid to operate the piston therein, a valve member disposed at the entrance to said conduit and engaged by the piston in said first cylinder to be held open when the piston is in home position, means for releasably'holding said piston in home position, means operated by said shoe carriage to release said holding means after predetermined travel of said carriage, and means effective upon release of said valve means following travel of said first piston to close the Valve against return flow from said second cylinder.

10. An .ironingmachine comprising a frame, a cylinder supported therein, a piston in said cylinder, a buck on said piston, means for discharging fluid under pressure forwardly of said piston to propel the same from a home position to an operating position, a shoe, a carriage for said shoe pivoted relative to the buck and swingable to bring the shoe into registry with the buck, a second cylinder fixed relative to the frame, a piston in said cylinder for swinging the carriage into said registering position, conduit means interconnecting said cylinders to feed said second cylinder with fluid to operate the piston therein, valve means in said conduit,-means for releasably holding said first piston in home position, means carried by said first piston operable upon movement thereof to home position to 9 10 open said valve means, means operated by said REFERENCES CITED shoe carriage to release said holding means after predetermined travel of said carriage and The following references are of record in the means responsive to movement of said first pisfile of thls patent: ton after the release thereof to close said conduit 5 UNITED STATES PATENTS valve means against return flow of liquid from Number Name Date sald secmd cylmder- 2,135,266 Wardwell, Jr. Nov. 1, 1938 JOSEPH C. WCRS-T. CARL S. DAYTON. 

